Swinging cutter cutting-off tool



June 24, 1930. A. L. sEGx-:LHRST 76718 SWINGING CUTTER CUTTINGOFF TOOLv Filed sept. so, 1922 2 Asheets-sham 1 Patented June 24, 11930 l UNITED S11-Aires PATENT omen AUGUs'r L. sEGELnoRsT', or wnrrmrnn, CALIFORNIA, AssIGNon or ONE-HALF To WALTERQ. BLAcmxor wnrr'rrnn., CALIFORNIA '-swINeING' GUTTER ourrma-Orr`Toor.

Application medsepember 30,1932. serial 1ro.' 591,543.

. My invention relates to rotary wellv drilling I equipment and relates particularly to cutvting off tools'by which pipe may be cut off within a well. 1

It occurs in the drilling of wells byrotary :system that the drilling tool and a portion of the drill pipe are sometimes lost-in the well."

This losing of the tool and drill pi e may be due either to the twisting oif of t e pipe or its becoming disconnected within thefwell,

the former being of most common occurrence.

When a drill pipe twists E, or becomes otherwise disconnected, the sand willilow around the lower end thereof and the lubricating mud settle, owing to the loss ofy circulation, before an overshot can be lowered over the twisted 'ofi' pipe to raise it from the well. This collec- 'Ltion of sand prevents the lifting of thecasin tool it becomes necessary to wash out around `the submerged pipe and cut thatvportion thereof `projecting above the collected sand and then proceed to wash out another p ortion of thesand, thereupon cuttingl oft` another portion of the drill pipe; thereafter continuing this washing and cutting process until the drill bit is. reached and the sand washed away therefrom so that it can be removed.

It is a principal object of my invention to provide a simple yet eective form of cutting 0E tool which ma be lowered into the well, down over the submerged drill pipe to any desired point, and then rotated to acbomplish the cutting 0E of the pipe.

It is a further object of my invention to provide a device of this character having pivoted blades which are deflected by contact with obstructions upon the drill pipe such as couplings or collars so that the tool may be lowered overthe drill pipe to thedesired point of cutting.

The especial advantages of my invention and further objects thereof will be made evident hereinafter.

Referring to the drawings, which are for illustrative purposes only,

Fig. 1 is a sectional view illustratingthe manner in which the cutters of the tool are deected by contact with a collar as the tool annular projection 13 formed integral with said member extends inwardly into the bore is lowered, over a submerged string of drill pi e 2 is a Vfragmentary section illustrating the movement offene ofthe cutters upon its lplates employed in the device,

Flg.' 5 is a perspective view-of one of the 4cutting tools, and

Fig. `6V is a fragmentary enlarged section 'taken' upon a lane represented by the line 6 6- of Fig. 3 or the purpose of clearly illustrating the manner in which the cutting tool is engaged by the annular plates and thereby Iresiliently maintained in cutting position.

' In the construction of. my invention I ema tubular shell" member 11 having the thereof internally threaded as 'indicated thereof,vhavin notches or channels 14 cut therein as best Illustrated in Fig. 3, in which notches cutters 15l are pivoted upon pins 16 `which lie ina plane perpendicular to'the axis of the memberell. The cutters 115, as' shown in Fig. 5, are made from self-hardening tool steel in a form which provides a central bladeportion 20, having elongated cam shaped hubs 21 symmetrically extending from each lside therof, and are drilled as indicated at 22 to accommodate the pins 16 upon which they are pivoted in their respective slots 13. The hubs 21 are provided with lateral converging faces 23 which are engaged by lugs 25 formed upon annular plates 26 which are situated above and below the kannular projection 13 and are held resiliently, but forcibly, in engagement with the cutters 15 by stiff helical springs 28, which are compressed by the upper coupling member 30 and the guide shoe 31 which are threaded into the ends of the member 11, as shown in Figs. 1 and 2. The lugs 25 are formed'in pairs as shown at 33 in Fig. 4 and 'are so'placed as to straddle the blade portion 20 of each of the cutters 15, thus allowing the attened faces 35 thereof to bear directly upon the faces 23 of the cutting tool hubs 21.` The plates 26 are provided with hole 27, adapted to pass over centering Ipins 29, mounted in the inwardly projecting ring, 13. Y It will be seen due to the symmetrical( formation of the cam shaped hub 21, that the pressure of the springs 28 against the plates 26 holds the cutters normally inwardly extended as shown in Fig. 6, and provides a resistance against the cutting tools being rotated upon the pivot pins 16. The sprmgs acting through the plates 26, do not, however, prevent the cutters from rotating either upwardly or downwardly when suiicient pressure is exerted upon the extending, or cutting ends, thereof. This rotatable feature of the cutters is of particular utility when the cutting off tool is being lowered over the drill pipe, as shown in Fig. 1. When, in lowering the tool into the well upon the lower end of a string of pipe, the submerged drill pipe is encountered, the drill pipe is directed into the member 11 by the guide shoe 31. The upper1 endof the drill pipe 45 comes against the ends 40 of the cutters and delects them upwardly, causing them to rotate upwardly upon the pivot pins 16. The ends 40 of the cutters then ride along the surface of the drill pipe in the partially rotated positions shown in Fig. 1. Upon striking a collar 46, they are further deflected upwardly and pass on over the collar; dropping back into the position, in which they are shown, against the drill pipe, after the collar 46 1s passed. In this manner the tool may be lowered over the drill pipe to any desired point.

- When the point at which it is desiredfto cut olf the drill pipe is reached, the line of pipe to which the cutting off tool is attached is gripped in the-rotary table and rotated, which causes the rotation of the member'll upon the pipe 45.

It will be perceived from an inspection of Fig. 2, that with the pressure of the plates 26 against the cutters 15 under pressure of the springs 28, a force is continually exerted from both above and below which tends to .return the cutters 15 to their inwardly pointed positions as shown in Fig. 6; thus the cutting ends 40 of the blade portions 2O are maintained in forcible contact with the surface of the drill pipe 45, with the result that, when the member 11 is rotated, the cutting members 15 perform a cutting action upon the drill pipe and cut into the pipe in the form of a ring, as indicated at 50 in Fig. 2. As the material is removed in" the cutting of the drill pipe, the cutters 15'u1ider the pressure of the springs 28 are gradually rotated into the inwardly extending position indicated by the dotted lines 51, the lengthof the cutting `ends 40 being so proportioned that the drill pipe 45 will be cut entirely through, upon the cutting tools reaching this position.

For the purpose of lifting the severed portion of the drill pipe from the well, an overshot 55 may be inserted at any desired point in the length of pipe supporting the member 11. In the illustration I- have shown the overshot 55 installed directly above the member 11, and connected thereto by. means of a coupling collar 56.

I have found hat with the cutters in upwardly deflected position against the outside of a submerged pipe, the upward movement l of the member 11 will cause the cutting ends 40 of the cutters to penetrate the casing and swing downwardly upo`n the pins 16, thereafter sliding along the face of thecasing and over collars as the member 11 is lifted upwardly, in the same manner as when the device was lowered over the drill pipe.

A cutting off tool of this character may be Very cheaply manufactured and the blades thereof, as required for renewal purposes, may b e very economically produced. The springs 28 may be provided of such strength as to give a very strong cutting pressure of the tool against the casing without preventing the cutters from rotating, as described, to permit the passage of the tool up or down over a string of drill pipe. In illustrating and describing my inventlon I present a form having springs operating from both above and below. In my experiments I have ascertained that such a tool will operate satisfactorily with a single spring only, placed above or below; but in order to provide additional cutting pressure to the cutters, I desire to employ two springs, as shown.

I claim as my invention:

1. In a cutting-olf tool: the combination of a rotatable tubular body; a series of inwardly extending cutters pivotally mounted on said body in substantially the same horizontal plane and opposed compression springs mounted in said body for resiliently holding the cutting edges of said cutters 2. In a cutting-oifftool the combination of a rotatable tubular body; pivot members mounted in said body in positions transverse with relation to the axis of said body at substantially the same horizontal level; a seriesy 'a plane' perpendicular to .the axis of said body; cutters pivoted on said pivot members inwardly in engagement with the pipe to be in inwardly projecting positions and arranged to swing'in planes substantially parallel to said axis of said body; and plate members resiliently held against the upper and lower faces of said cutters, in a manner causing said cutters to be normally maintained in laterally projecting positions and resiliently displaceable to either an upwardly' or downwardly projecting position.

4. In a cutting-oil tool adapted to operate at any pointupon the outside surface of a pipe; a rotatable cutting tool body; inwardly extending substantially symmetrical cutters pivotally mounted in said body and inwardly swingable in planes substantially parallel with the axis of said body; and spring means for normally forcing said cutters into resil- Aientlyprojecting positions in which positions said cutters are continuously in pressure con-v tact with the 'surface of the pipe u on which the cutting operation is to be per ormed.

In testimony whereof, I have hereunto set my hand at Los Angeles, California, this 19th day of September, 1922.

. AUGUST L. SEGELHORST.

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